//: Playground - noun: a place where people can play
/*
 第一章代码
 */
import UIKit

var str: String = "Hello, playground"
var number = 12
var rate:Double = 12.0
var rate1 = 12.0
var score = 20
score += 3

let a = 3
let b = 2
let result = a + b

print("胜率为\(rate)%")
